static bool IsChoosable(this IGraph_uint graph, uint[] colorGraph, uint liveVertexBits, int c, Dictionary <BitLevelGeneration.HashedAssignment_uint, bool> cache, ref long nodesVisited, ref long cacheHits)
{
nodesVisited++;
graph.BeGreedy(colorGraph, ref liveVertexBits, c);
if (liveVertexBits == 0)
{
return(true);
}
if ((liveVertexBits & ~colorGraph.Or(c)) != 0)
{
return(false);
}
//bool cachedResult;
//var key = new BitLevelGeneration.HashedAssignment_uint(colorGraph, c, liveVertexBits);
//if (cache.TryGetValue(key, out cachedResult))
//{
// cacheHits++;
// return cachedResult;
//}
var choosable = false;
var V = colorGraph[c] & liveVertexBits;
foreach (var C in graph.MaximalIndependentSubsets(V))
{
if (graph.IsChoosable(colorGraph, liveVertexBits ^ C, c + 1, cache, ref nodesVisited, ref cacheHits))
{
choosable = true;
break;
}
}
//cache[key] = choosable;
return(choosable);
}
